Variable condenser



p 1939. J. ANTONIETTA 2,172,725

VARIABLE CONDENSER Filed Feb. 5, 1936 MA I I! WNTOR,

ATTORNEY.

Patented Sept. 12, 1939 UNITED STATES PATENT OFFICE VARIABLE CONDENSER Joseph Antonletta, Port Richmond, Staten Island,

Application February 5, 1936, Serial No. 62,402 2 Claims. (01. 175-415) This invention relates to devices such as frame or mounting structures for instruments and the like; also to plate carrying shafts; and has particular reference to electrical devices such as 5 variable condensers.

One object of the invention is to provide a device of the character described having improved mounting means operative without the use of rivets, screws or the like, which not only require extra machine operations and increase the cost of assembling the device, but also allow slippage, looseness and vibration to occur due to imperfections in the assembling or variations caused by stresses or changes in temperature of the metal parts.

Another object of the invention is to furnish a device of the nature set forth having improved mounting means adapted for assembling in quantity production and which will allow for mechanicai variations in course of assembly, and maintain the several parts interconnected by a clamping action never to my knowledge used heretofore in the association described and claimed herein.

Another object of the invention is to furnish a device of the type specified wherein the operating unit, such as the stator of a variable condenser, may be initially assembled with insulator means therefor, and the latter connected to a metallic mounting frame in course of moving the said unit into assembly relation in the frame.

Another object of the invention is the provision of a device of the class alluded to wherein an instrument clamping channel is utilized as an element of superior structural strength in uniting parts of a frame for mounting the unit.

Another object of the invention is to provide a device of the character described having a plurality of different parts held by individual rela- 49 tively resilient clamping action by interengagement with a single member which may desirably constitute a beam, column, strut, spacer, tie bar, shaft or the like of a frame structure.

Another object of the invention is the provision of a device of the character described having improved means comprising a plurality of elements one of which is grooved or channeled and engageable with the other element in said groove by a relative movement along the plane of the 50 latterpif desired, said latter element may be up set in the groove to increase the holding engagement, preferably an element is thicker than the groove so as to be resiliently clamped therein without material distortion of either to thus cause accuracy to be maintained.

Another object of the invention is to construct a connecting element as for a stator or other member of an electrical instrument adapted to afford a terminal therefor, and mounting the member on an insulator plate by being connected to the latter in such manner as to be irremovable except upon disconnection from said member; considered from another view, the connecting element may be engaged with the insulator plate or part without the use of screws, rivets or the like, avoiding looseness and vibration of the member that is mounted.

In a broad sense, it is therefore an object of the invention to provide a device, such as, illustratively, a condenser stator, and an insulator plate where improved means clampingly secures the stator to the plate and the latter in turn to a frame to thus avoid vibration throughout with attendant advantages in quantity production.

Another object of the invention is to provide a shaft for a series of plates, where the shaft includes spaced holding means of a slotted plate receiving type, and intermediate spaced and offset portions of the grooved type to hold the plates rigid and against bending or tilting; differently stated, the object is to avoid through cutting or punching out of openings intermediate the edges of a shaft, as in the back of a channel shaft, and instead to press or punch grooves thereinto, which can be accomplished with a simple die having greater strength and longer life than a through cutter, and resulting in a shaft of greater strength and having plate receiving openings or grooves free of burrs, which may occur in through cutting, and which therefore permit greater accuracy in assembling the plates.

Another object of the invention is to furnish a sheet metal pressed shaft having parallel end ears or bearing portions to one-of which is axially connected an actuator element or stub shaft as for a knob, whereby the same shaft can be assembled with any of difierent stub shafts for different knobs.

A further object of the invention is to provide a device as set forth having relatively few and simple parts and which is inexpensive to manufacture and assemble, durable, reliable and efficient to a high degree in use; also an improved method for making and assembling the device and its parts.

This application is an improvement over my U. S. Patent No. 1,972,510 issued September 4, 1934, for Variable tuning condensers, and is also an improvement over my pending application, Serial No. 696,472, flied November 3, 1933,

for Variable tuning condensers, as a division of said patent and which has matured into U. S. Patent No. 2,046,994, issued July 7, 1936.

Other. objects and advantages of the invention will become apparent as the specification proceeds.

With the aforesaid objects in view. the invention consists in the novel combinations and arrangements of parts hereinafter described in their preferred embodiments, pointed out in the subjoined claims, and illustrated in the annexed drawing, wherein like parts are designated by the same reference characters throughout the several views.

In the drawing:

Figure 1 is a view in end elevation with parts removed and in section, showing a device enrbodying the invention.

Fig. 2 is a similar view in side elevation thereof.

Fig. 3 is a similar top plan view thereof.

Fig. 4 is a transverse sectional view of'the shaft embodying the invention, with a plate shown in dot-dash lines.

Fig. 5 is a bottom plan view of the shaft with only certain of the plates secured thereto.

Fig. 6 is a fragmentary sectional view taken on the line 6-6 of Fig. 2.

The advantages of the invention as here outlined are best realized when all of its features and instrumentallties are combined in one and the same structure, but, useful devices may be produced embodying less thanthe whole.

It will be obvious to those skilled in the art to which the invention appertains, that the same maybe incorporated in several diflerent constructions. The accompanying drawing, therefore, is submitted merely as showing the preferred exempliilcation of the invention.

Referring in detail to the drawing, l0 denotes a device embodying the invention. While the same is shown embodied in a variable tuning condenser, the latter is intended to be illustrative of the applicability of the invention to different devices and machines, both large and small, and particularly of electrical instruments or the like, where insulation may be required, and also of such instruments whether electrical or not where freedom from vibration is required and the devices must be capable of manufacture and installation on a quantity production basis for more or less wide or general use.

The device I0 may include a frame it which may comprise a plurality of spaced end members or plates l2, l3, and a plurality of spaced interconnecting members therefor, such as, for instance, lower members and upper members such as I5. The latter may be omitted. In this manner a skeletonized frame is produced that is relatively light in weight, and which affords access for connections thereinto and for inspec tion and repair.

Mounted within the frame H is a member such as a stator I6, with which there may cooperate a rotor IT. The stator may comprise a plurality of like equally spaced parallel plates I8 interconnected in a unit by any suitable means such as conventional holding plates I9 having open-= lugs to receive lugs 20 of the stator plates, which lugs may be upset. The rotor may include a plurality of like equally spaced parallel plates 2| alternately interleaved with the stator plates in spaced relation thereto. In a variable condenser the rotor plates 2! may be suitably mounted on any shaft, such as 22, the stator plates being cut away as at 23 to allow .clearance for said shaft. In the case of an eccentric type of variable condenser shown, the portions of the rotor plates remote from the shaft may desirably be interconnected by a reenforcing or stop plate such as 24 having openings to r ive lugs 25 of the rotor plates, and which lugs ay vice must be rugged and reliable to prevent initial or any later stresses from causing a distortion that may cause such contact, and to avoid the labor in bending or straightening plates in assembling; and further, the device ought to be free of vibrations which may affect condenser operation or capacity, and which may be caused by improper cushioning or tightness of Joints, or may result of alternate expansion and contraction of parts due to temperature variation.

With the foregoing in mind, it will be noted that the operative part of the instrument, including stator and rotor, has a line or axis transverse to the end plates l2, l3. Desirably the stator 46 is mounted on the frame elements H, v

and the rotor l8 on the end plates l2, l3. Preferably, the elements l4 may be regarded as carried by the end plates l2, It.

The stator I 6 may be mounted on the frame members I I as by insulating means of any suitable size, shape or structure, and which may be comprehensively indicated by the term plates, such as shown at 26, and which can conveniently be connected to the stator at the holding plates l9 thereof. The relationship between the members I4 and 26 is such that one set of the members clampingly engages the other. Since the plates 26 are desirably relatively parallel to each other, the said engagement may be effected simultaneously for both plates, or by relative vertical pressure. If the plates 26 be initially connected to the stator, the latter may in this manner be inserted into the frame ll coincident with the mounting of the plates 28. Howeven'it is preferable to first mount the plates 26, and then to connect the stator thereto.

Preferably the members I! constitute channel members of any suitable shape or structure, desirably uniform throughout, as indicated by the relatively plane parallel flanges 21 thereof, which may define longitudinal continuous upward opening channels, grooves or recesses. These channel members I 4 may be suitably connected at their ends to the plates l2, iii. For instance, the flanges 21 may have individual like end prongs or projections, those of the inner flanges shown at 28 being received in like openings 29 of the plates l2, l3 and being upset and expanded, while those of the outer flanges shown at 30 being received in like recesses 3| of the plates l2, l3, the edges of said openings at the edges of said plates being upset or deformed as at 32. The bottom or back portions 33 of the channel members afford abutment shoulders for spacing the end plates l2, I3, and the prongs 28, 30 may afford shoulder portions 34 for a like purpose. Thus the channel members l4 may be duplicates of each other, and

may be used at either side of the condenser so alike, except that the positions of the terminal that rights and lefts are unnecessary, and the end plates l2, ll being rapidly reliably and rigidly interconnected.

By forming the members H as channel members, a high degree of strength in the frame is obtained consistent wth minimum weight, and connection with the end plates at spaced points at each end of the channel members is obtained for superior rigidity.

At a point intermediate of the ends of the channel members, each of them may have one or more cut outs such as 45, to provide sections such as 36 and 21 for clampingly securing a plurality of parts with individual clamping stress, and so as to reduce the tendency of a stress at one section from affecting or reducing the clamping power, at another section. These cut outs 35, however, terminate in spaced relation to the backs 33 of the channel members, so as not to unduly weaken the flanges 21 thereof. Specifically, the functions of the sections 36, 31 is illustrated by the use of a plurality of stators l6 as shown, each having its individual insulator plates 26 clampingly secured in individual sections 36. There may, of course, be a corresponding plurality of rotors or rotor sections |I all mounted on the shaft 22. Thus there are, in effect, a plu- .rality of variable condensers combined in a unitary structure, and desirably separated as by a frame plate 55, which may have an opening 59 to clear the shaft 22, and lugs such as at the ends thereof for clamping engagement in the sections 31 of the channel members. The arrangement may be such that the plate 38 may have the same length and height as the end plates l2, l3 for uniformity and affording shoulder engagement with the edges of the flanges 21, with the end and bottom edges of plates |2, II and 38 lying flush with corresponding adjacent surfaces of the channel members.

Additional strength for the frame may be provided by the bar elements |5 which may engage the elements !2, l3 as by clamping portions furnished on one set of these elements. Thus the bars l5 may be transversely grooved or undercut or formed with necks as at 4|, the end plates l2, l3 having openings 42 to snugly receive the undercut portions, adjacent portions of the structure such as edges of said plates being punched or upset as at 43 to wedglngly secure the bars l5 against disengagement. It is noted that the bars l5 are desirably made of half round stock whereby a saving in weight and material is obtained, and, more important still, a lesser amount of space is utilized as compared with ordinary round stock, strength of the frame being maintained, and an easier assembling with greater accuracy of the frame effected. Like the channel members H, the bars |5 are duplicates of each other. .Their flat faces lie in the planes of the side edges of the end plates I2, I! and afford neatness and reliable gripping surfaces for holding the frame in assembling or repair work. All of the plates l2, I3 and 36 may be connected to the bars l5 in the manner described.

For mounting the stator |6 on the insulator elements 26. and preferably, also, to afford terminal lugs for the stator, I utilize a means comprising elements which cooperate clampingly with the elements 26, as by providing one set of these elements with clamping portions. Preferably, plates or conductor portions 44 are provided, which may have terminal lugs 45 and lie on the outside of the insulators 26 for easy accessibility. All of the plates 44 may be exactly lugs 45 may be different. Each plate 44 may have one or more integral projections or strap portions 45, for instance, at the lower edge thereof, adapted to pass through openings 41 in the insulator plates 26, the ends of said portions 46 being suitably, for instance, autogenousiy connected as at 48 to the holding plates IQ of the stator. Thus the main body of the plate 44 forms a head or anchorage which, as it is too large to pass through opening 41, prevents disconnection of the stator except by breaking the autogenous connection.

Desirably the plates 44 are mounted on and fully connected to the plates 26 before the latter are clamped to the frame II.

To obtain a perfectly rigid relation between the plates 44 and 26, I provide a clamping means including one or more elementssuch as projections 46 engaged as in holes" of the insulator plates 26 to cause the elements to individually prevent relative vertical or horizontal movement in any direction. -The clamping means also comprise one or more projections or prongs such as 49 which form parts of plates and, for speed in assembling extend from the ends thereof to be bent around end edges of the insulator plates, desirably as in recesses 50 thereof to thus prevent any relative angular movement between the plates. In mounting the stator, the same is set in predetermined relation to the frame I I by any suitable gage, and the stator is then soldered at 48 to the straps 46.

The autogenous connection at 48 may be made after the insulator plates 26 have been mounted in the channel members I4.

An adjusting or secondary condenser may be provided according to conventional practise. This condenser may consist of a plate 5| of thin resilient metal, lying along the outside of the plate 44 and adjustable toward and away therefrom as by a set screw 52 which may pass freely through holes 53, 54 respectively in the plates 5| and 44 and having threaded connection with the insulator plates as shown. Holes for the set screws 52 may be provided in all of the plates 26 and 44 for use as desired.

The principal feature of the adjusting condenser 5| is that it is mounted in a novel manner as by being clamped in a channel member l4. For example, a condenser plate 5| and an insulator plate 26 may be pressed as a unit into a channel member to be thus simultaneously secured therein. Thus reliable securement is obtained and loosening and vibration avoided. While the channel members or the insulator plates 26 may be of varying widths or thicknesses, desirably they may be all alike, and the channel members may consist of a resilient material adapted to yield sufllciently to snugly hold either the plates 26 alone, or plates 26 and 5| together. The sectional clamping as at 36, 31 is an advantage in the assembling of the adjusting condenser. The plate 5| is very thin, and, if necessary, the insulator material of the plates 26 may yield under the powerful clamping action of the channel members. I prefer, however, to make the insulator members of a material such as hard, pressed fiber, Bakelite or the like, and the channel members ,of a relatively mild steel which shall not be unduly expensive, but the walls of the channel members being quite thick for powerful clamping.

For certain purposes the channel members |4 may be squeezed or clamped on the plates 26,

to clampingly secure the latter, but in general,

it is preferred to use fully preformed channel members.

It is noted that the terminal or mounting plates 44 may be utilized as the complemental condenser elements for the plates The shaft 22 of the rotor I! may be of pressed sheet material to afford a channel or other strong structural shape. Thus said shaft may have a back 55, flanges 56, and the latter may be provided with longitudinal outward extending marginal lips 51 which may constitute holding means for the rotor plates 2| as by being transversely slotted at 58 or otherwise provided with any kind of openings for receiving portions of the rotor plates. The back 55 may have openings such as grooves 59 to receive adjacent portions of the rotor plates for afiording lateral support for the rotor plates along a plane offset from that of the lips 51. The rotor plates are in general cut out to receive the channel shaft, and to afford edge portions for engaging in the alined slots and grooves 58, 59.

For securing the rotor plates 2| in the shaft 22, the latter is punched or deformed intermediate of the rotor plates. Thus the back 55 is punched at 60, and the lips 51 are punched as at 6|, thus expanding the metal at the openings 58, 59 to tightly grip the rotor plates. The

.punches at 60, 6| may be made simultaneously all along the shaft for balanced stress due to the deformations produced.

The advantage in forming grooves 59 instead of through openings in the back of the channel is that it is easier and cheaper to provide the grooves. Due to the narrowness of the openings, a punching tool for forming through openings is necessarily weaker and will be subject to greater wear than one which forms the grooves by pressing or cutting the same. Moreover, a punched hole may leave a slight burr, whereas the grooves 59 will afford a uniform, accurate seat for the rotor'plates. Since the latter are powerfully secured in the slots 58, the engagement at the grooves 59 is rather for maintaining the plates in parallelism than for securing the plates to the shaft. This constitutes a novel inventive concept.

The shaft 24 as thus produced is of superior strength because the back 55 is imporforate, and

hence this shaft may also be more true, as it is better adapted to take up stresses along the lip 57 incident to the punching at 6i. The said shaft may also possess some degree of resilience,

so that the rotor plates are gripped in a manner which will not be affected by expansion and contraction of the metal. Heretofore, with other shafts, the rotor plates have sometimes become loosened, apparently for the reason in .part, that when the shafe contracts, the rotor The shaft 22 may have integral parallel end cars such as 62, 63 for mounting the shaft. To the car 62, a stub shaft 84 maybe connected as by riveting an undercut endportion 65 of the stub shaft thereto. Thus different typesof sizes of stub shafts may be axially secured to a standard shaft 22, the stub shafts varying with the different sizes or styles of knobs or actuators that may be employed.

For journallng the shaft 22 on the frame Ii, the end plae l3 may have a recessed bearing por-- tion 66 through which the undercut end part 65 of the stub shaft passes, an annular series of balls 61 seating in the recess 66 about the part 65, and the bearing being completed as by a washer or annular member 68, which need not be affected by the riveting of the stub shaft 84 to the shaft 22.

The ear 63 may be perforated as at 69 to provide a seat for a ball 'Hl'the complemental seat being afforded by a set screw II threaded into the end plate l2 and secured with a locknut 12. Clearance may be taken up by a leaf spring I3 secured to the end plate l2 at 14 and having a forked portion 15 receiving the bearing ball, said spring being bowed intermediate 01' its ends as shown.

In assembling the device, the plates 26 may be first engaged with the channel members l4, and then the stator connected to the plates 44 which may have been initially assembled with the insulator plates 26. Or, the stator may be wholly assembled with plates 26 and the latter then attached to members l4, especially if 'the members l5 be omitted or spaced further apart for clearance. In making the shaft 22, the different plate openings may be punched simultaneously and the plates then assembled with the shaft. The openings 58, 59 may all be slotted or grooved, or as shown, or in vice versa relation. After the stub shaft 64 is connected to the shaft 22, the rotor is mounted in the frame I l and then the stator mounted in the said frame.

I claim:

1. A condenser including a condenser unit comprising a plurality of spaced condenser plates, a frame including a plurality of spaced end membore, a plurality of spaced channel members constructed of sheet metal affording yieldable flanges, said channel members each having their different flanges provided with individual end projections, said and members having openings in which said and projections are secured, and means for mounting said condenser unit. in said channel members, including insulator plates press fitted in said channel members.

2. A condenser including a condenser unit comprising a, plurality of spaced plates, a frame including spaced end plates and spaced sheet metal channel members interconnecting said plates, said unit having insulator members of brittle material connected thereto, said insulator members being clampingly press fitted in the individual channel members between the flanges thereof, said flanges being yieldable so as to avoid breakage of the insulator members on forcing the same into the channel members.

JOSEPH rlNTONIETTr-i. 

